Anionic surfactants are essential in various applications, especially detergency. Anionic surfactants with carboxylic acid moieties have been used for thousands of years; soap was first made from the hydrolysis of naturally-occurring oils/fats. Fatty acid surfactants have an excellent combination of properties including low CMC, low surface tension at the CMC, good foaming characteristics and mildness when applied to skin. However, the 20th century has seen the use of these surfactants relative to other anionic surfactants decrease significantly. The most significant disadvantage of carboxylate surfactants as opposed to other anionic surfactants is their propensity to precipitate when divalent cations, e.g., calcium and magnesium, are present; in other words carboxylate surfactants have inferior hardness tolerance. Thus, there is a need for new carboxylate anionic detergents with high solubility and good hardness tolerance.